Of course Bernal's views of crystals that he first photographed was that the molecular structure must be long and thin, and...

[Q] And this he deduced simply from the character of the crystal cell?

Yes, the character of the crystal cell, and the optics, the direction of the optic axes. Who from that point the chemists, particularly Rosenheim and King, who had been interested in his work, took a new look at all the chemical evidence, and they particularly were working on the hydrogenation of the sterols to give hydrocarbons, of which... amongst which one was chrysene, and he thought there might be sterol skeletons and might really be something like chrysene with a long chain attached to it. That wasn't right, but it was along the right idea. We could find that, eventually when we worked on cholesterol... iodines, is it?

[Q] This is it here.

But the sterol rings are similar to pycene ring systems. They're shown by this model and we could see, get a projection of the structure down this short axis easily from the reflections we measured. And then, with considerable difficulty, the three-dimensional electron density by calculations done at right angles, selected lines through the apparent atomic positions. And this work was really done by Bernal's research students at Birkbeck. Harry Carlyle, when he came to Oxford to work with me, Bernal himself was called away to work on air raid precautions the moment the war began, and he sent more apparatus, two X-ray tubes, and our apparatus to Oxford, together with research students. Harry Carlyle, who was an 1851 scholar from India, from Lucknow in India, and Katie Dornberger, who had already taken her doctor's degree in Vienna, but had just begun to work with Goldschmidt, a very well-known German X-ray crystallographer, who was Jewish, and they were just warned to escape from their lab, so Goldschmidt went to Norway, to Oslo, where he also held a professorship, and Katie came straight across to Bernal's lab, and she worked for some time on a small research job, and then she came over and did calculations with me on insulin. So she was very useful to me.

British pioneer of X-ray crystallography, Dorothy Hodgkin (1910-1994), is best known for her ground-breaking discovery of the structures of penicillin, insulin and vitamin B12. At age 18, she started studying chemistry at Somerville College, Oxford, then one of the University of Oxford colleges for women only. She also studied at the University of Cambridge under John Desmond Bernal, where she became aware of the potential of X-ray crystallography to determine the structure of proteins. Together with Sydney Brenner, Jack Dunitz, Leslie Orgel, and Beryl Oughton, she was one of the first people in April 1953 to see the model of the structure of DNA, constructed by Francis Crick and James Watson. She was awarded the 1964 Nobel Prize in Chemistry and is also known for her peace work with organisations such as Science for Peace and the Medical Aid Committee for Vietnam. All recorded material copyright of The Biochemical Society.

Guy Dodson studied chemistry and physical science at the University of New Zealand, followed by a PhD on the crystallographic study of an alkaloid. In 1961, he came to Oxford to work on the crystal structure of insulin. In the mid 1970s Guy and his wife moved to York University to establish a laboratory. In addition to insulin studies the laboratory has investigated many complex molecules of medical significance, including haemoglobin, myoglobin, HIV related proteins, proteases and proteins involved in managing nucleic acids in cells. In 1993, he went to the NIMR in London to establish a crystallographic group in an environment that spanned molecular, physiological and disease-related disciplines. Here his research began on some cell signalling proteins. His interests on medically relevant proteins included prions, malarial and TB proteins, and some clinically relevant thrombin inhibitors. Guy Dodson retired in 2004 but is still finding much to do in York and the NIMR.